A pressure-contact semiconductor device realizes increased power density by two-surface heat release, and high reliability under a high voltage and a large current. A pressure-contact semiconductor device has a structure wherein a semiconductor element inside an insulating frame body is sandwiched by upper and lower electrode blocks and hermetically sealed. Internal electrical contact is maintained by a pressing force being exerted on the upper and lower electrode blocks from the exterior.
A pressure-contact semiconductor device is such that, even when an internal semiconductor element breaks down, the semiconductor device itself short-circuits without being damaged. Because of this, there is an advantage in that redundant design is easy, such as by using pressure-contact semiconductor devices connected in series so that operation is possible without immediately stopping the system even after the breakdown of a semiconductor element.
However, when an overload state continues with a broken down semiconductor element, fusion of the semiconductor element occurs due to a temperature rise, and there is concern that the internal pressure of the pressure-contact semiconductor devices will rise, ultimately resulting in a possible explosion. If explosion occurs, fragments of the semiconductor device scatter, which will likely damage circuits and cooling devices on the periphery of the semiconductor device, and there is concern that the system will become inoperative.